Posting comments on relevant blogs are also a good way to create backlinks. If search engines find your links on other related sites, they will consider your link to give a higher rank. So start commenting.
At first you have to find relevant blogs. For this purpose you can search on google by typing keyword ‘top blogs on seo’ or ‘top 100 blogs on seo’ or ‘ best blogs on seo’ – if your niche is ‘seo’. You can also use google blog search. Or search related blogs on several high quality directories.
Many blogs comment sections are ‘dofollow’ and some other are ‘nofollow’. The term ‘dofollow’ means search engines will consider the links for ranking and ‘nofollow’ means search engines wil not count these links for their ranking. Normally ‘nofollow’ status imposed where spammers irritate more. So you should commenting on ‘dofollow’ blogs. Normally ‘dofollow’ blogs give a separate box to give your web url. If you can get this box, there is no need to put url’s on your comment. Putting url on comments most time considered as spamming. People hate spammers so don’t be a spammer.
Give comments after reading blog don’t give this types of comment ‘very good blog’, ‘very well written’ or ‘thanks for sharing’. Try to write several lines about this blog. It will bring more benefit to you.